Cryptocurrencies are a nascent asset class and could fall violently at any time, the founder of blockchain network Ethereum warned on Saturday.

“Reminder: cryptocurrencies are still a new and hyper-volatile asset class, and could drop to near-zero at any time,” Vitalik Buterin said on Twitter. “Don’t put in more money than you can afford to lose.”

Buterin added: “If you’re trying to figure out where to store your life savings, traditional assets are still your safest bet.”

In December, the Ethereum creator compared wild investment in the cryptocurrency market to the record sum paid for the world’s most expensive painting, Leonardo Da Vinci’s “Salvator Mundi.”

Ethereum is a blockchain network; blockchain is the technology that underpins cryptocurrencies. It maintains a continuously growing record of cryptocurrency transactions across a decentralized network. The digital token of the Ethereum network is called ether, but it is also often referred to as ethereum.